relibc_pthreads-emb/cleanup.c

/*
 * cleanup.c
 *
 * Description:
 * This translation unit implements routines associated
 * with cleaning up threads.
 *
 *
 * --------------------------------------------------------------------------
 *
 *      Pthreads-embedded (PTE) - POSIX Threads Library for embedded systems
 *      Copyright(C) 2008 Jason Schmidlapp
 *
 *      Contact Email: [email protected]
 *
 *
 *      Based upon Pthreads-win32 - POSIX Threads Library for Win32
 *      Copyright(C) 1998 John E. Bossom
 *      Copyright(C) 1999,2005 Pthreads-win32 contributors
 *
 *      Contact Email: [email protected]
 *
 *      The original list of contributors to the Pthreads-win32 project
 *      is contained in the file CONTRIBUTORS.ptw32 included with the
 *      source code distribution. The list can also be seen at the
 *      following World Wide Web location:
 *      http://sources.redhat.com/pthreads-win32/contributors.html
 *
 *      This library is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU Lesser General Public
 *      License as published by the Free Software Foundation; either
 *      version 2 of the License, or (at your option) any later version.
 *
 *      This library is distributed in the hope that it will be useful,
 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *      Lesser General Public License for more details.
 *
 *      You should have received a copy of the GNU Lesser General Public
 *      License along with this library in the file COPYING.LIB;
 *      if not, write to the Free Software Foundation, Inc.,
 *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */

#include "pthread.h"
#include "implement.h"


/*
 * The functions pte_pop_cleanup and pte_push_cleanup
 * are implemented here for applications written in C with no
 * C++ destructor support.
 */

pte_cleanup_t *
pte_pop_cleanup (int execute)
/*
 * ------------------------------------------------------
 * DOCPUBLIC
 *      This function pops the most recently pushed cleanup
 *      handler. If execute is nonzero, then the cleanup handler
 *      is executed if non-null.
 *
 * PARAMETERS
 *      execute
 *              if nonzero, execute the cleanup handler
 *
 *
 * DESCRIPTION
 *      This function pops the most recently pushed cleanup
 *      handler. If execute is nonzero, then the cleanup handler
 *      is executed if non-null.
 *      NOTE: specify 'execute' as nonzero to avoid duplication
 *                of common cleanup code.
 *
 * RESULTS
 *              N/A
 *
 * ------------------------------------------------------
 */
{
  pte_cleanup_t *cleanup;

  cleanup = (pte_cleanup_t *) pthread_getspecific (pte_cleanupKey);

  if (cleanup != NULL)
    {
      if (execute && (cleanup->routine != NULL))
        {

          (*cleanup->routine) (cleanup->arg);

        }

      pthread_setspecific (pte_cleanupKey, (void *) cleanup->prev);

    }

  return (cleanup);

}				/* pte_pop_cleanup */


void
pte_push_cleanup (pte_cleanup_t * cleanup,
                  pte_cleanup_callback_t routine, void *arg)
/*
 * ------------------------------------------------------
 * DOCPUBLIC
 *      This function pushes a new cleanup handler onto the thread's stack
 *      of cleanup handlers. Each cleanup handler pushed onto the stack is
 *      popped and invoked with the argument 'arg' when
 *              a) the thread exits by calling 'pthread_exit',
 *              b) when the thread acts on a cancellation request,
 *              c) or when the thread calls pthread_cleanup_pop with a nonzero
 *                 'execute' argument
 *
 * PARAMETERS
 *      cleanup
 *              a pointer to an instance of pthread_cleanup_t,
 *
 *      routine
 *              pointer to a cleanup handler,
 *
 *      arg
 *              parameter to be passed to the cleanup handler
 *
 *
 * DESCRIPTION
 *      This function pushes a new cleanup handler onto the thread's stack
 *      of cleanup handlers. Each cleanup handler pushed onto the stack is
 *      popped and invoked with the argument 'arg' when
 *              a) the thread exits by calling 'pthread_exit',
 *              b) when the thread acts on a cancellation request,
 *              c) or when the thrad calls pthread_cleanup_pop with a nonzero
 *                 'execute' argument
 *      NOTE: pthread_push_cleanup, pte_pop_cleanup must be paired
 *                in the same lexical scope.
 *
 * RESULTS
 *              pthread_cleanup_t *
 *                              pointer to the previous cleanup
 *
 * ------------------------------------------------------
 */
{
  cleanup->routine = routine;
  cleanup->arg = arg;

  cleanup->prev = (pte_cleanup_t *) pthread_getspecific (pte_cleanupKey);

  pthread_setspecific (pte_cleanupKey, (void *) cleanup);

}				/* pte_push_cleanup */